Discovery and Characterization of a Novel Bacteriocin HA2-5 that Strongly Inhibits Propionibacterium acnes

Increased drug resistance has significantly reduced theeffectivenessof antibiotics used in the treatment of Propionibacteriumacnes. Therefore, there has been a trend toward thedevelopment of new antimicrobial agents to circumvent drug resistance.In this study, we isolated and purified a novel bacteriocin, HA2-5,from Bacillus haynesii HA2, which effectivelykilled P. acnes through membrane disruptionat a minimum inhibitory concentration (MIC) of 8 & mu;g/mL. HA2-5with 2x MIC was able to kill 99.9% of P. acnes within 24 h. HA2-5 shows excellent stability and tolerance to temperature,pH, proteases, chemical reagents, UV radiation, and metal ions, withalmost no loss of inhibitory activity after treatment. In addition,the very low hemolytic activity and cytotoxicity suggest that HA2-5is biosafe. Notably, HA2-5 exhibits preferred antibacterial activityagainst gram-positive pathogens with an MIC of 16-32 & mu;g/mL.In conclusion, this study shows that bacteriocin HA2-5 has the potentialto be used as an alternative to antibiotics for acne treatment.

Automated summary

In this study, a novel bacteriocin, HA2-5, was isolated and purified from Bacillus haynesii HA2, which effectively killed Propionibacterium acnes through membrane disruption. HA2-5 exhibited excellent stability and tolerance to various conditions and showed preferred antibacterial activity against gram-positive pathogens. These findings suggest that bacteriocin HA2-5 has the potential to be used as an alternative to antibiotics for acne treatment.